883 resultados para Cutting Edge
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The mechanisms responsible for the immunosuppression associated with sepsis or some chronic blood infections remain poorly understood. Here we show that infection with a malaria parasite (Plasmodium berghei) or simple systemic exposure to bacterial or viral Toll-like receptor ligands inhibited cross-priming. Reduced cross-priming was a consequence of downregulation of cross-presentation by activated dendritic cells due to systemic activation that did not otherwise globally inhibit T cell proliferation. Although activated dendritic cells retained their capacity to present viral antigens via the endogenous major histocompatibility complex class I processing pathway, antiviral responses were greatly impaired in mice exposed to Toll-like receptor ligands. This is consistent with a key function for cross-presentation in antiviral immunity and helps explain the immunosuppressive effects of systemic infection. Moreover, inhibition of cross-presentation was overcome by injection of dendritic cells bearing antigen, which provides a new strategy for generating immunity during immunosuppressive blood infections.
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Objective. NKT cells have diverse immune regulatory functions including activation of cells involved in Th1- and Th2-type immune activities. Most previous studies have investigated the functions of NKT cells as a single family but more recent evidence indicates the distinct functional properties of NKT cell subpopulation. This study aims to determine whether NKT cell subpopulations have different stimulatory activities on other immune cells that may affect the outcome of NKT cell-based immunotherapy. Methods. NKT cells and NKT cell subpopulations (CD4(+)CD8(-), CD4(-)CD8(+), CD4(-)CD8(+)) were cocultured with PBMC and their activities on immune cells including CD4(+) and CD8(+) T cells, NK cells, and B cells were assessed by flow cytometry. The production of cytokines in culture was measured by enzyme-linked immunsorbent assay. Results. The CD4(+)CD8(-) NKT cells demonstrated substantially greater stimulatory activities on CD4(+) T cells, NK cells, and B cells than other NKT cell subsets. The CD4(-)CD8(+) NKT cells showed the greatest activity on CD8(+) T cells, and were the only NKT cell subset that activated these immune cells. The CD4(-)CD8(-) NKT cells showed moderate stimulatory activity on CD4(+) T cells and the least activity on other immune cells. Conclusion. The results here suggest that NKT cell subpopulations differ in their abilities to stimulate other immune cells. This highlights the potential importance of manipulating specific NKT cell subpopulations for particular therapeutic situations and of evaluating subpopulations, rather than NKT cells as a group, during investigation of a possible role of NKT cells in various disease settings. (c) 2006 International Society for Experimental Hematology. Published by Elsevier Inc.
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Modern procurement is being shifted from paper-based, people-intensive buying systems toward electronic-based purchase procedures that rely on Internet communications and Web-enhanced buying tools. Develops a typology of e-commerce tools that have come to characterize cutting-edge industrial procurement. E-commerce aspects of purchasing are organized into communication and transaction tools that encompass both internal and external buying activities. Further, a model of the impact of e-commerce on the structure and processes of an organization's buying center is developed. The impact of the changing buying center on procurement outcomes in terms of efficiency and effectiveness is also analyzed. Finally, implications for business-to-business marketers and researchers are discussed.
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Modern distribution is being shifted from paper-based, people-intensive marketing systems toward electronic-based procedures that rely on Internet communications and web-enhanced software tools. This article develops a typology of e-business technological innovations that have come to characterize cutting-edge distribution management. e-Business tools relevant to marketing channels are organized by the channel process flows that yield communication and transaction enhancements to distribution systems. Further, a model of the impact of e-business on channel performance is developed. The mediating role of channel structure on technology's impact on channel outcomes in terms of efficiency and effectiveness is also analyzed. Finally, implications of the e-business revolution for managers and researchers are discussed.
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What is the nature of our current societies? Do we see a clash of civilizations, or the end of history? The advent of globalization, or the birth of the network society? Are we witnessing the emergence of a risk society, or the advent of the knowledge society? More fundamentally, is ‘society’ an ideological construct that should be abandoned? Coming into English from the Latin term ‘societas’ via Old French ‘société’, the etymology of ‘society,’ in the sense of a system adopted by a group of co-existing individuals for mutually beneficial purposes, can be traced back at least to the mid-sixteenth century. By the Age of Enlightenment, ‘society’ was increasingly used in intellectual discourse to characterize human relations, often in contrast to notions of ‘the state’. During the nineteenth century, the concept was subject to highly elaborate treatment in various intellectual fields, such as political economy, philosophy, and legal thought; and ‘society’ continues to be a central conceptual tool, not only for sociology, but also for many other social-science disciplines, such as anthropology, economics, political sciences, and law. The notion resonates beyond the social sciences into the humanities; it is a fundamental concept, like nature, the universe, or the economy. Moreover, ‘society’ remains a highly contested concept, as was demonstrated, for example, by the controversy surrounding the former British prime minister Margaret Thatcher’s pithy assertion of the neoliberal economic wisdom that ‘there is no such thing as society’ (Woman’s Own, 31 October 1987); and by the term’s rehabilitation at the turn of the twenty-first century, not least with the ascendancy of the notion of ‘civil society’. This four-volume collection, a new title in the Routledge Critical Concepts in Sociology series, brings together both canonical and the best cutting-edge research to document the intellectual origins and development of what remains a key framework within which contemporary work in the social sciences in general, and sociology in particular, proceeds. Edited by Reiner Grundmann and Nico Stehr, two leading scholars in the field, this Routledge Major Work makes available the most useful, important and representative treatments of the subject matter, and helps to make sense of the great variety of perspectives and approaches in which social scientists and other thinkers have understood, and continue to understand, society. Fully indexed and with a comprehensive introduction newly written by the editors, which places the collected material in its historical and intellectual context, Society is an essential reference work, destined to be valued by scholars and students as a vital research resource.
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The main objective of the work presented in this thesis is to investigate the two sides of the flute, the face and the heel of a twist drill. The flute face was designed to yield straight diametral lips which could be extended to eliminate the chisel edge, and consequently a single cutting edge will be obtained. Since drill rigidity and space for chip conveyance have to be a compromise a theoretical expression is deduced which enables optimum chip disposal capacity to be described in terms of drill parameters. This expression is used to describe the flute heel side. Another main objective is to study the effect on drill performance of changing the conventional drill flute. Drills were manufactured according to the new flute design. Tests were run in order to compare the performance of a conventional flute drill and non conventional design put forward. The results showed that 50% reduction in thrust force and approximately 18% reduction in torque were attained for the new design. The flank wear was measured at the outer corner and found to be less for the new design drill than for the conventional one in the majority of cases. Hole quality, roundness, size and roughness were also considered as a further aspect of drill performance. Improvement in hole quality is shown to arise under certain cutting conditions. Accordingly it might be possible to use a hole which is produced in one pass of the new drill which previously would have required a drilled and reamed hole. A subsidiary objective is to design the form milling cutter that should be employed for milling the foregoing special flute from drill blank allowing for the interference effect. A mathematical analysis in conjunction with computing technique and computers is used. To control the grinding parameter, a prototype drill grinder was designed and built upon the framework of an existing cincinnati cutter grinder. The design and build of the new grinder is based on a computer aided drill point geometry analysis. In addition to the conical grinding concept, the new grinder is also used to produce spherical point utilizing a computer aided drill point geometry analysis.
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From the challenges of sustainability to disruptive technology, work environments face unprecedented change and this major new textbook provides a cutting-edge introduction to how psychology and the world of work interact. Leading international academics, Steve Woods and Mike West, combine the latest research with truly global perspectives to leave students with a fully-rounded understanding of work psychology. Developed from wide-ranging lecturer feedback, three key themes of Ethics and Social Responsibility, Globalization and Cross-cultural Issues, and Environment and Sustainability are threaded throughout every chapter, while an attractive full-colour design and engaging pedagogical devices stimulate student interaction on this rapidly growing course. A full set of lecturer resources including Instructors Manual, PowerPoint Slides and Test Bank make this the complete resource for modern work psychology courses.
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After thirty years of vacillation, the Tanzanian government has made a firm decision to Swahilize its secondary education system. It has also embarked on an ambitious economic and social development programme (Vision 2025) to transform its peasant society into a modern agricultural community. However, there is a faction in Tanzania opposed to Kiswahili as the medium of education. Already many members of the middle and upper class their children to English medium primary schools to avoid the Kiswahili medium public schools and to prepare their children for the English medium secondary system presently in place. Within the education system, particularly at university level, there is a desire to maintain English as the medium of education. English is seen to provide access to the international scientific community, to cutting edge technology and to the global economy. My interest in this conflict of interests stems from several years' experience teaching English to students at Sokoine University of Agriculture. Students specialise in agriculture and are expected to work with the peasant population on graduation. The students experience difficulties studying in English and then find their Kiswahili skills insufficient to explain to farmers the new techniques and technologies that they have studied in English. They are hampered by a complex triglossic situation in which they use their mother tongue with family and friends, Kiswahili, the national language for early education and most public communication within Tanzania, and English for advanced studies. My aim in this thesis was - to study the language policy in Tanzania and see how it is understood and implemented; - to examine the attitudes towards the various languages and their various roles; - to investigate actual language behaviour in Tanzanian higher education. My conclusion is that the dysfunctionality of the present study has to be addressed. Diglossic public life in Tanzania has to be accommodated. The only solution appears to be a compromise, namely a bilingual education system which supports from all cases of society by using Kiswahili, together with an early introduction of English and its promotion as a privileged foreign language, so that Tanzania can continue to develop internally through Kiswahili and at the same time retain access to the globalising world through the medium of English.
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Key features include: • Discussion of language in relation to various aspects of identity, such as those connected with nation and region, as well as in relation to social aspects such as social class and race. • A chapter on undertaking research that will equip students with appropriate research methods for their own projects. • An analysis of language and identity within the context of written as well as spoken texts. Language and Identity in Englishes examines the core issues and debates surrounding the relationship between English, language and identity. Drawing on a range of international examples from the UK, US, China and India, Clark uses both cutting-edge fieldwork and her own original research to give a comprehensive account of the study of language and identity. With its accessible structure, international scope and the inclusion of leading research in the area, this book is ideal for any student taking modules in language and identity or sociolinguistics.
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The United Nations has pithily defined sustainable development as progress that ‘meets the needs of the present without compromising the ability of future generations to meet their own needs’. But sustainable development remains highly contested and is subject to a wide variety of interpretations, applications, and criticisms. Moreover, those seeking fully to understand this critical concept are confronted with a (sometimes dispiritingly) voluminous body of scholarly, polemical, and journalistic writing. Edited by the acclaimed author of Understanding Sustainable Development (Earthscan, 2008), this new title from Routledge’s Critical Concepts in the Environment series answers the need for an authoritative reference work to make sense of the vast literature on sustainable development, and the continuing explosion in research output. Drawing on a wide variety of sources that take full cognizance of the rich background and necessary adaptability of the concept to the imperatives of time, place, and culture, and which emphasize its connected and transdisciplinary nature, the editor has brought together in four volumes the canonical and the best cutting-edge work to produce an indispensable ‘mini library’. The collection covers the history, mediation, application, and likely future orientations of sustainable development, both conceptually and as a continually emerging practice. Sustainable Development is fully indexed and includes comprehensive introductions, newly written by the editor, which place the collected materials in their historical and intellectual context. It is an essential reference collection and is certain to be valued by scholars and students—as well as serious policy-makers and practitioners—as a vital one-stop research and pedagogic resource.
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Цветомир Цачев - В настоящия доклад се прави преглед на някои резултати от областта на оптималното управление на непрекъснатите хетерогенни системи, публикувани в периодичната научна литература в последните години. Една динамична система се нарича хетерогенна, ако всеки от нейните елементи има собствена динамиката. Тук разглеждаме оптимално управление на системи, чиято хетерогенност се описва с едномерен или двумерен параметър – на всяка стойност на параметъра отговаря съответен елемент на системата. Хетерогенните динамични системи се използват за моделиране на процеси в икономиката, епидемиологията, биологията, опазване на обществената сигурност (ограничаване на използването на наркотици) и др. Тук разглеждаме модел на оптимално инвестиране в образование на макроикономическо ниво [11], на ограничаване на последствията от разпространението на СПИН [9], на пазар на права за въглеродни емисии [3, 4] и на оптимален макроикономически растеж при повишаване на нивото на върховите технологии [1]. Ключови думи: оптимално управление, непрекъснати хетерогенни динамични системи, приложения в икономиката и епидемиолегията
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Innovation is the driving force that is crucial for firms to sustain their competitive advantage and for economies and industries in general to surge forward. In comparison to developing economies, developed economies have always maintained greater focus on national innovation systems while the firms from these economies have been investing considerable effort on promoting organisational innovation. As firms became increasingly global, consumers across the world, especially from the emerging economies, are getting a taste of more sophisticated products and services. There was also an infusion of knowledge pertaining to cutting-edge technologies, innovation, processes and management systems into this part of the world. However, studies on organisational innovation have largely been confined to firms from developed economies in order to understand the effects of its determinants (Anderson et al., 2004; Choi and Williams, 2014; Li et al., 2013). Given the differences in the socio-cultural milieu between the developed and emerging economies, more nuanced understanding of the factors affecting and the processes associated with innovation in emerging markets is required.
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Over the past few decades, we have been enjoying tremendous benefits thanks to the revolutionary advancement of computing systems, driven mainly by the remarkable semiconductor technology scaling and the increasingly complicated processor architecture. However, the exponentially increased transistor density has directly led to exponentially increased power consumption and dramatically elevated system temperature, which not only adversely impacts the system's cost, performance and reliability, but also increases the leakage and thus the overall power consumption. Today, the power and thermal issues have posed enormous challenges and threaten to slow down the continuous evolvement of computer technology. Effective power/thermal-aware design techniques are urgently demanded, at all design abstraction levels, from the circuit-level, the logic-level, to the architectural-level and the system-level. ^ In this dissertation, we present our research efforts to employ real-time scheduling techniques to solve the resource-constrained power/thermal-aware, design-optimization problems. In our research, we developed a set of simple yet accurate system-level models to capture the processor's thermal dynamic as well as the interdependency of leakage power consumption, temperature, and supply voltage. Based on these models, we investigated the fundamental principles in power/thermal-aware scheduling, and developed real-time scheduling techniques targeting at a variety of design objectives, including peak temperature minimization, overall energy reduction, and performance maximization. ^ The novelty of this work is that we integrate the cutting-edge research on power and thermal at the circuit and architectural-level into a set of accurate yet simplified system-level models, and are able to conduct system-level analysis and design based on these models. The theoretical study in this work serves as a solid foundation for the guidance of the power/thermal-aware scheduling algorithms development in practical computing systems.^
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Optimizing GIS capability does not always require that the municipality obtain cutting edge professionals and resources. This paper offers a disaster risk reduction (DRR) design methodology for small towns and rural areas that employs a multi-variable classification system, enabling customization for effective DRR. Determining appropriate GIS capacity requires that a community first be evaluated in order to identify its disaster risk reduction/disaster management (DRR/DM) requirements. These requirements are then considered in conjunction with the municipality's resources to establish the desired capability. Qualification levels for major aspects of GIS capability with respect to DRR/DM are provided along with descriptions of each level and suggested procedures for advancement to the next level. It should be noted that a municipality can be classified at a different level with respect to different variables. Needs vary according to the community, thus attainment of a uniform capability level may not be necessary.
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Around the world borders are militarized, states are stepping up repressive anti-immigrant controls, and native publics are turning immigrants into scapegoats for the spiraling crisis of global capitalism. The massive displacement and primitive accumulation unleashed by free trade agreements and neo-liberal policies, as well as state and “private” violence has resulted in a virtually inexhaustible immigrant labor reserve for the global economy. State controls over immigration and immigrant labor have several functions for the system: 1) state repression and criminalization of undocumented immigration make immigrants vulnerable and deportable and therefore subject to conditions of super-exploitation, super-control and hyper-surveillance; 2) anti-immigrant repressive apparatuses are themselves ever more important sources of accumulation, ranging from private for-profit immigrant detention centers, to the militarization of borders, and the purchase by states of military hardware and systems of surveillance. Immigrant labor is extremely profitable for the transnational corporate economy; 3) the anti-immigrant policies associated with repressive state apparatuses help turn attention away from the crisis of global capitalism among more privileged sectors of the working class and convert immigrant workers into scapegoats for the crisis, thus deflecting attention from the root causes of the crisis and undermining working class unity. This article focuses on structural and historical underpinnings of the phenomenon of immigrant labor in the new global capitalist system and on how the rise of a globally integrated production and financial system, a transnational capitalist class, and transnational state apparatuses, have led to a reorganization of the world market in labor, including deeper reliance on a rapidly expanding reserve army of immigrant labor and a vicious new anti-immigrant politics. It looks at the United States as an illustration of the larger worldwide situation with regard to immigration and immigrant justice. Finally, it explores the rise of an immigrant justice movement around the world, observes the leading role that immigrant workers often play in worker’s struggles and that a mass immigrant rights movement is at the cutting edge of the struggle against transnational corporate exploitation. We call for replacing the whole concept of national citizenship with that of global citizenship as the only rallying cry that can assure justice and equality for all.